Bent and Linear {CoNO}(8) Entities: Structure and Bonding in a Prototypic Class of Nitrosyls

Popp, Jens; Riggenmann, Tobias; Schröder, Daniel; Ampssler, Torsten; Salvador, Pedro und Klüfers, Peter (2021): Bent and Linear {CoNO}(8) Entities: Structure and Bonding in a Prototypic Class of Nitrosyls. In: Inorganic Chemistry, Bd. 60, Nr. 21: S. 15980-15996

Abstract

Among the isoelectronic ligands CN-, CO, and NO+, an oblique bonding to the metal is well-established for the nitrosyl ligand, with M-N-O angles down to similar to 120 degrees. In the last decades, the nitrosyl community got into the habit of addressing a bent-bonded nitrosyl ligand as (NO-)-N-1. Thus, because various redox forms of a nitrosyl ligand seem to exist, the ligand is considered to be noninnocent because of the obvious ambiguity of an oxidation state (OS) assignment of the ligand and metal. Among the bent-bonded species, the low-spin {CoNO}(8) class is prototypic. From this class, some 20 new nitrosyl compounds, the X-ray structure determinations of which comply with strict quality criteria, were analyzed with respect to the OS issue. As a result, the effective OS method shows a low-spin d(8) Co-I-NO+ couple instead of a negative OS of the ligand at the BP86/def2-TZVP (+D3, +CPCM with infinite permittivity) level of theory. The same holds for some new members of the linear subclass of {CoNO}(8) compounds. For all compounds, a largely invariable real charge of approximate to-0.3 e was obtained from population analyses. All of these electron-rich d8 species strive to manage Pauli repulsion between the metal electrons and the lone pair at the nitrosyl's nitrogen atom, with the bending of the CoNO unit as the most frequent escape.

• Dokumententyp: Zeitschriftenartikel
• Fakultät: Chemie und Pharmazie > Department Chemie
• Themengebiete: 500 Naturwissenschaften und Mathematik > 540 Chemie
• ISSN: 0020-1669
• Sprache: Englisch